TUF 4 has begun shooting, and no fighters have been confirmed, but MMA Weekly published a list of rumored fighters, some interesting names in the mix:
http://www.mmaweekly.com/absolutenm/templates/dailynews.asp?articleid=2111&zoneid=13
In the middleweight division, the eight fighters are rumored to be Jorge Rivera, Patrick Cote, Charles McCarthy, Gideon Ray, Mark Weir, Travis Lutter, Edwin Dewees, and 48-year-old UFC 1 veteran Keith Hackney.
In the welterweight division, the eight fighters are rumored to be Matt Serra, Chris Lytle, Shonie Carter, Rich Clementi, Mikey Burnett, Pete Spratt, Nick Diaz, and Din Thomas.
http://www.mmaweekly.com/absolutenm/templates/dailynews.asp?articleid=2111&zoneid=13